1. Field of the Invention
The present invention pertains to the field of random number generators and, in particular, to a digital data processing apparatus and method for generating true binary random sequences.
2. Description of the Related Art
Random-number generators are fundamentally important in this computer age. A truly random sequence is difficult to generate in real application. For example, heat is typically generated in the hardware component of the random number generator when it generates a series of 1's and 0's over a time period. Generating a 1 bit could consume more power than a 0 bit. As such, if a long sequence of 1 bits is generated, the electrical circuit becomes hot. Thus, if the circuit generates a 1 bit when it is hot, the circuit will “latch up” and generate mostly 1 bits but rarely a 0 bit. A different effect may occur if a 0 bit is generated when the circuit is hot. In this case a long sub-sequence of 1 bits becomes too rare and constitutes a non-random property. In random sequences where occasionally long sub-sequences consist of equal bits of long 0's or 1's, the biased 0/1 frequency error will have catastrophic consequences of breaching security.
Accordingly, both the detection of hardware tampering and a component failure are necessary when conducting randomness tests. Conventional randomness tests are performed through extensive statistical testing, such as chi-squared tests, delta tests, and the like, on a sequence of generated random numbers. However, such tests are very expensive to be performed in real time as they require a great amount of computational processing power.